1. Field of the Invention
This invention relates generally to microelectronic element chips, and processes for their fabrication.
2. Related Art
Myriad microelectronic elements have been formed on conductive wafers such as silicon wafers. Multiple such devices may be formed on a single wafer, which then may be diced to separate the devices as chips. A single chip may contain a number of microelectronic elements integrated into a circuit.
As this vast chip technology continues to evolve, the potential magnitude of conductor interconnections between a chip and further circuitry with which the chip may be integrated accordingly continues to grow. Implementation of early chip technology included the practice of bonding wire conductor interconnections on top of microelectronic elements formed on the chip. With ever greater multiplicity of potential conductor interconnections with a chip, direct chip attachment (“DCA”) technology has been developed, including provision of conductor interconnections that may pass through the chip itself from one side of the wafer to the other. However, the need for sufficient conductor interconnections for the large numbers of microelectronic elements that may be formed on a single chip constitutes a continuing problem, and a limitation in chip design.
There is a continuing need for new types of chip structures for direct chip attachment that may facilitate further growth in the potential magnitude of microelectronic elements to be formed on a chip, and a need for processes that facilitate the fabrication of such chip structures.